<!DOCTYPE html>
<html lang="en">
<head>
  <meta charset="UTF-8">
  <meta http-equiv="X-UA-Compatible" content="IE=edge">
  <meta name="viewport" content="width=device-width, initial-scale=1.0">
  <title>Document</title>
</head>
<body>
  
  <script>
     function takeSubscript(a,b,c,d,e,f){
      let arr=[a,b,c,d,e,f]
      let n=-1
      for(let i=0;i<arr.length;i++){
        if(arr[i]===10){
          n=i;
        }
      }
      console.log(n);
     }

     takeSubscript(88,20,90,100,50)

  </script>
</body>
</html>